Many people know what it’s like to feel sad or down from time to
time.

We can experience negative emotions due to many things - a bad day
at work, a relationship break-up, a sad film, or just getting out of
bed on the “wrong side”.

Sometimes we even say that we’re feeling a bit
“depressed”. But what does that mean, and how can we tell when it’s more
than just a feeling?

Depression is more than the experience of sadness or stress.

A depressive episode
is defined as a period of two weeks or longer where the individual
experiences persistent feelings of sadness or loss of pleasure, coupled
with a range of other physical and psychological symptoms including
fatigue, changes in sleep or appetite, feelings of guilt or
worthlessness, difficulty concentrating or thoughts of death.

To be diagnosed with major depressive disorder, individuals must
experience at least one depressive episode that disrupts their work,
social or home life.

Because it’s highly prevalent and can be significantly disabling, the World Health Organization
reports that depression is the third highest cause of disease burden
worldwide, with a greater burden on the community than heart disease.
There are also high levels of overlap between depression and other
common mental disorders, including anxiety and substance use disorders.

Unfortunately, only 35%
of people with symptoms of mental health problems seek help. This may
be because of difficulties identifying depression in the community due
to a lack of knowledge or accessing care, and stigmatising attitudes
towards depression.

Depression prevention programs that provide accessible treatments,
increase knowledge and change negative attitudes are an important way to
increase access to treatment and reduce the burden of depression.

Causes and risk factors

There’s generally no single reason why an individual becomes
depressed. There’s a constellation of risk factors, including
physiological, genetic, psychological, social and demographic
influences.

Biological risk factors include having a family history of
depression, suffering a long-term physical illness or injury,
experiencing chronic pain, using illicit drugs or certain prescription
medications, chronic sleep problems, or having a baby. Having
experienced depression in the past is a risk factor for a further
depressive episode.

Psychological risk factors for depression include having low self-esteem, or having a tendency to be self-critical. Demographic and social influences
include being female (women are almost twice as likely to suffer from
depression than men), stressful life events (such as relationship
conflict or caring for someone with an illness), experiencing a
difficult or abusive childhood, or being unemployed.

People differ greatly in the amount or type of risk factors they’re
exposed to or experience. And having several risk factors alone is not
enough to trigger depression.

A combination of risk factors and the experience of stressful or
adverse life events may prompt the onset of depression. The greater the
number of risk factors that a person experiences, the more vulnerable
they are to developing depression when stressful life events occur.

In contrast, those exposed to fewer risk factors are somewhat
buffered, and may only develop depression when exposed to extreme levels
of environmental stress.